xxxxxxxxxx
# List updates without installing them
sudo snap refresh --list
# Update all packages/snaps
sudo snap refresh
# Update only PACKAGE
sudo snap refresh PACKAGE
xxxxxxxxxx
sudo snap refresh
Will do this. It is part of snapd 2.0.8, which landed 2016-06-13 in xenial-updates.
snap refresh --list
Only lists the updates without refreshing the packages.
snap info
Can show which versions are available for a particular package.
You can also update a specific application if the other method fails
sudo snap refresh
Example usage:
sudo snap refresh slack --classic